1. Field of the Invention
The present invention relates to methods of transferring indicia from one surface to another, and in particular, the present invention relates to an economical method of producing an indicia transferring surface. Also disclosed is a method of producing surfaces having raised areas in the form of said indicia.
2. Description of the Prior Art
In the prior art, there are many methods of transferring indicia from one surface to another. Three basic methods are lithographic printing, gravure printing, and letter press printing.
In lithographic printing, the transferring surface or the printing gate has a light-sensitive coating on its surface. Portions of the coating which have been subjected to light are washed away by a selective solvent. The coating that is left on the lithographic plate is in the form of indicia and attracts ink, the ink having been transferred to the plate from another surface. The ink is then transferred from the lithographic plate to the desired surface. As is readily seen from the above description, the lithographic process involves a substantial amount of equipment and considerable cost.
In the gravure printing process, the indicia transferring surface or the printing plate uses recessed areas to transfer the desired indicia to another surface. The recessed areas are formed by various engraving processes most of which require substantial cost and equipment.
The letter press process relies on raised areas to transfer ink from the transferring surface or plate to printing surface. The raised areas or type face are usually molded and then placed next to each other on the transferring surface or plate to form the desired indicia for transferring. This method, like the first two printing methods, also involves considerable cost and requires a substantial amount of equipment for transferring indicia from one surface to another.
Other methods of transferring indicia from one surface to another include engraving, etching and embossing. Engraving, generally involves the formation of grooves in a flat surface with a tool, the grooves being the shape of the indicia desired for transferring.
Etching involves coating a metal surface with an acid-resistant coating and scratching the coating in the form of indicia, then contacting the surface with an acid, the acid eating into the metal surface and leaving the impression of the indicia to be transferred to another surface.
Embossing is a process that merely stamps the desired impression or indicia into a thin flat plate made of plastic or metal, raising the surface on the other side, the raised surfaces being used to transfer the desired indicia to another surface.
Engraving and etching involve a considerable amount of craftsmanship and embossing generally involves an embossing machine or a chisel-type tool. Engraving, etching and embossing are slow processes and embossing is limited to transferring surfaces having fairly thin thicknesses.
There are many applications wherein the above-mentioned methods are not suitable for transferring indicia either because of economic costs or physical limitations of the method itself. One such example is the marking of electrical components for identification purposes. Using any of the three above-mentioned printing processes for identification marking of electric components would be very costly because of the equipment needed to transfer indicia to the surface of the electrical component. Engraving, etching or embossing an identification marking into an electrical component are too slow to be economically efficient. What is needed is a method of producing an indicia transferring surface that does not require a substantial amount of equipment or craftsmanship, and yet is economically efficient.